Barrel break in

@Shootist43 , excellent comments, particularly on first cleaning of a new used rifle.

This is straight off of Krieger's website, even though they hand lap their barrels, they recommend barrel break in. I am waiting on a Krieger barrel for my 404 Jeff project and when I get the gun from the gunsmith doing the job (Dennis Olson in MT), I will go through the break in procedure.

https://kriegerbarrels.com/about

SINGLE-POINT CUT-RIFLING
We rifle all of our barrels using the single-point cut-rifling process. Although our machines are state-of-the-art, the process itself is the oldest and slowest method of rifling a barrel. It’s also the most accurate. The cutter removes approximately .0001 inch, or 1 ten-thousandth of an inch, at each pass, thus taking several hundred passes to rifle a barrel. This method produces almost perfect concentricity between bore and groove, a very uniform twist rate, and induces no stress into the steel that later has to be relieved. Along the same lines, we do absolutely no straightening of our barrels as this would only put stress right back into the steel.

Our barrels are lapped after reaming to remove the tool marks, and then hand-lapped again after rifling. It has been said that if a barrel is cut-rifled correctly, it does not have to be finish lapped, and to some extent this is true. It should not have to be lapped to obtain uniformity of dimensions. This should come from the tooling and procedures used. But there is a slight improvement to the finish achieved by finish lapping, and the lay of the finish is now in the direction of the bullet travel so fouling is greatly reduced, and cleaning is made easier. It takes longer to finish lap, but we do it because it makes a better barrel. We are lapping to finishes under 16 micro-inch in the direction of the bullet travel. In contrast the government requires only a 32 micro-inch finish on its M-14 National Match barrels.
 
@Shootist43 , excellent comments, particularly on first cleaning of a new used rifle.

This is straight off of Krieger's website, even though they hand lap their barrels, they recommend barrel break in. I am waiting on a Krieger barrel for my 404 Jeff project and when I get the gun from the gunsmith doing the job (Dennis Olson in MT), I will go through the break in procedure.

https://kriegerbarrels.com/about

SINGLE-POINT CUT-RIFLING
We rifle all of our barrels using the single-point cut-rifling process. Although our machines are state-of-the-art, the process itself is the oldest and slowest method of rifling a barrel. It’s also the most accurate. The cutter removes approximately .0001 inch, or 1 ten-thousandth of an inch, at each pass, thus taking several hundred passes to rifle a barrel. This method produces almost perfect concentricity between bore and groove, a very uniform twist rate, and induces no stress into the steel that later has to be relieved. Along the same lines, we do absolutely no straightening of our barrels as this would only put stress right back into the steel.

Our barrels are lapped after reaming to remove the tool marks, and then hand-lapped again after rifling. It has been said that if a barrel is cut-rifled correctly, it does not have to be finish lapped, and to some extent this is true. It should not have to be lapped to obtain uniformity of dimensions. This should come from the tooling and procedures used. But there is a slight improvement to the finish achieved by finish lapping, and the lay of the finish is now in the direction of the bullet travel so fouling is greatly reduced, and cleaning is made easier. It takes longer to finish lap, but we do it because it makes a better barrel. We are lapping to finishes under 16 micro-inch in the direction of the bullet travel. In contrast the government requires only a 32 micro-inch finish on its M-14 National Match barrels.

Krieger is who I plan on using for my 577 NE falling block build. Prior, I've tended to use Pac-Nor pre-fit barrels (for Ruger No.1 conversions, namely to the big Nitro Express calibers), but as the 577 is a design all my own, built from scratch, I've decided to go with Krieger.

Regarding breaking in a barrel, I've only bothered on the really small calibers.
 
Krieger is who I plan on using for my 577 NE falling block build. Prior, I've tended to use Pac-Nor pre-fit barrels (for Ruger No.1 conversions, namely to the big Nitro Express calibers), but as the 577 is a design all my own, built from scratch, I've decided to go with Krieger.

Regarding breaking in a barrel, I've only bothered on the really small calibers.

You may know this already, but Krieger quotes 5-6 months for delivery. I ordered my barrel the beginning of February. I'm going to drop them a note right after July 4th and ask them if we're getting close. BTW, they will ship the barrel direct to the gunsmith.
 
I think generally on custom barrels one wants to do the break in so that any remaining roughness (mostly in the throat) is burnt off and rifling is somewhat burnished. This should make it more consistent and easier to clean later. Factory chro-mo barrels take a bit longer, yet even the custom stainless barrels may really start shooting after one to two hundred rounds through it. Again, other people's experiences may be different and I'm no expert. In general I would agree that any lapping/breaking in, etc, wears the barrel so maybe just shooting it is the way to go...hahaha... Then again if it takes quite a few rounds to really break it in, does it really matter how we get to that point? As someone already mentioned, it is impossible to do the same barrel twice and since each barrel is different, it's hard to tell what really works best. I do not go through enough barrels to tell and the hunting rifles seem to mostly shoot fine regardless of break-in or affinity for copper or they shoot like crap from get-go.


P.S. Ha, just read the post above that quoted Kreiger. Their procedures and explanations make most sense to me. Since I use Kreiger barrels, I follow their advice. I may try to not break-in the next one but so far I had good results by doing it (barrel cleans easy after just few shots) and since it is only few shots, I don;t mind doing it.
 
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You may know this already, but Krieger quotes 5-6 months for delivery. I ordered my barrel the beginning of February. I'm going to drop them a note right after July 4th and ask them if we're getting close. BTW, they will ship the barrel direct to the gunsmith.

From Kreiger, sometimes one can find an in stock barrel that meets their needs. If it isn't the desired contour, they can cut it for you and thus reduce the waiting time.

https://kriegerbarrels.com/overruns
 
Some of my most accurate rifles are oldies that didn't have any "break in". However, breaking in barrels started to become the thing to do about ten years ago. So I started a clean after every shot for the first ten. Then after every three shot group for five groups and the after every six shots for another three. To be honest, I haven't seen a difference. But to be "safe", I'll continue breaking in. It's a PITA but other than that, there's little to no down side. Besides... I'm retired. What else do I have to do?
 
Here is what outdoor writer John Barsness has said numerous times:


"The one-shot-clean method of barrel break-in was developed by benchrest shooters so their barrels would be shooting at their best BEFORE their first match. If you feel the need to have your hunting rifle's barrel shooting 1/8" smaller groups before it kills its first deer, then why by all means go ahead and clean and shoot for umpteen rounds.

If not, a typical factory barrel will be as broken in as it will ever get if you simply clean it down to bare steel between range sessions.

Custom barrels don't really need break-in. In fact I know some barrel-makers who include a break-in procedure on their website ONLY because clients demand it. They got tired of explaining to potential customers why break-in wasn't necessary, when the customers "knew" it was because they heard it from their cousin at the shooting range.

The only part of a custom barrel that really needs smoothing is the reamer marks in the throat, because they run perpendicular to the bore. These can be eliminated much faster and easier, however, with a couple of fire-lapping bullets."
 
See, I'm lazy. For my last new barrel, the break in procedure consisted of a thorough clean of the bore, 1 round of cheapy PPU ammo down, a thorough clean, 3 more rounds of the same to get a preliminary zero, a thorough clean of the bore and then to use up the other 16 of the box on a short range 'non precision' competition discipline (in this case a running boar comp at 55yds).

After that, I gave it a thorough clean and began my load development.

Seems to work fine. I reckon the first shots do smooth some of the roughness, and you certainly get noticeably less copper build up after the following 16 shots than the first one, so that's something I guess. There also doesn't seem to be a lot of point trying to go straight into load development until it's had a few rounds down and a rudimentary sight in, so it doesn't actually 'cost' me any barrel life either. Worth noting that I didn't win the comp, but I don't think I can blame the new barrel for that...

As with many things shooting, I believe that the real benefit of barrel break in is psychological, but it can't do (much) harm, so crack on I reckon.
 
Here is what outdoor writer John Barsness has said numerous times:


"The one-shot-clean method of barrel break-in was developed by benchrest shooters so their barrels would be shooting at their best BEFORE their first match. If you feel the need to have your hunting rifle's barrel shooting 1/8" smaller groups before it kills its first deer, then why by all means go ahead and clean and shoot for umpteen rounds.

If not, a typical factory barrel will be as broken in as it will ever get if you simply clean it down to bare steel between range sessions.

Custom barrels don't really need break-in. In fact I know some barrel-makers who include a break-in procedure on their website ONLY because clients demand it. They got tired of explaining to potential customers why break-in wasn't necessary, when the customers "knew" it was because they heard it from their cousin at the shooting range.

The only part of a custom barrel that really needs smoothing is the reamer marks in the throat, because they run perpendicular to the bore. These can be eliminated much faster and easier, however, with a couple of fire-lapping bullets."
That guy better stick to writing. He doesn't know squat about rifle barrels or chambering. Fire lapping bullets? Good grief, just fill your bore with sand and fire a regular bullet. I hope know one ever followed his advice.
 
MMM, so many choices, so many options.

How about double rifles that have been regulated by the maker?
Several to many rounds down range from each barrel.
 
That guy better stick to writing. He doesn't know squat about rifle barrels or chambering. Fire lapping bullets? Good grief, just fill your bore with sand and fire a regular bullet. I hope know one ever followed his advice.

Fire lapping used to be all the rage, maybe 30-40 years ago. Then people came to realize the issues (why you wouldn't just cast a lead plug and do it by hand I never could understand...but, I suppose people are generally lazy and it's a lot easier (and maybe more fun) to send a few abrasive-laden bullets downrange).
 
You may know this already, but Krieger quotes 5-6 months for delivery. I ordered my barrel the beginning of February. I'm going to drop them a note right after July 4th and ask them if we're getting close. BTW, they will ship the barrel direct to the gunsmith.

Thanks for the heads-up. I do need to get around to ordering the barrel. I've got a customer contour I'd like and, if Krieger can produce it at a reasonable cost, I'm going to have them do so (which will only add to the time, I would think).
 
That guy better stick to writing. He doesn't know squat about rifle barrels or chambering. Fire lapping bullets? Good grief, just fill your bore with sand and fire a regular bullet. I hope know one ever followed his advice.

He forgot more than you'll ever know.
 
I like to run a patch down the barrel for the first ten rounds. It seems those initial shots tend to leave a lot of fouling. After that, whatever slight burns or imperfections in the bore that was causing such a mess gets smoother out.
I also subscribe to the theory that you clean a rifle after you shoot it, or take it out hunting for the day. Don’t leave dust and dirt on your optics, ect.
I have seen to many bores ruined by putting and or rust. Not a huge issue anymore with non corrosive primers and smokeless powder, but especially with black powder when I live, just overnight in the humidity can turn a barrel into a sewer pipe.
 
I like to run a patch down the barrel for the first ten rounds. It seems those initial shots tend to leave a lot of fouling. After that, whatever slight burns or imperfections in the bore that was causing such a mess gets smoother out.
I also subscribe to the theory that you clean a rifle after you shoot it, or take it out hunting for the day. Don’t leave dust and dirt on your optics, ect.
I have seen to many bores ruined by putting and or rust. Not a huge issue anymore with non corrosive primers and smokeless powder, but especially with black powder when I live, just overnight in the humidity can turn a barrel into a sewer pipe.

With black powder cleaning right after shooting is a must. The good part? Hot water is perfect for removing corrosive salts.
 
From another article about fire lapping bullets:
"You roll bullets, lead or jacketed, between two hard plates (steel usually) to embed valve grinding compound grit (generic term for lapping compounds you may be familiar with) into the bullets. Then generally with a reduced load, shoot these gritty bullets through the barrel.

It takes the tops off the surface finish inside the barrel going around the inside, and then leaves a finish going WITH the travel of the bullet. It also takes off burrs and sharp edges from the rifling.

And since the grit in the bullets breaks down as it travels down the barrel, the gritty bullets cut less and less as they travel toward the muzzle. Thus you get something of a "choked" bore & groove, and this in itself is a plus to accuracy. Barrels that get progressively tighter toward the muzzle are usually quite accurate. (As a side note, this is what you get with some "air gauged" barrels... they simply mark the tighter end "muzzle.")

David Tubb also advocates its periodic application to rifles shot a lot, the idea being to smooth up the rough, scorched surface in the throat of the barrel.

However, he also concedes that fire lapping INCREASES THE DIAMETER OF THE THROAT. And given that most all throats are cut larger than they should be, especially from factories, my contention is that while you may make temporary improvement in accuracy fire lapping existing barrels, you also wipe out potentially thousands of rounds of throat life by further enlarging it by fire lapping."

As I mentioned before. Tough to say. These guys shoot more than most of us ever will and they go through many barrels and they compare them, inspect them, etc. So I bet there is validity in their opinions. Do they apply to me and do they apply to hunting? Who knows. Maybe somewhat. Physics is physics - abrasion (hand lapping, breaking-in with regular bullets, fire lapping, etc.) will wear the material away. Questions is how much is a good amount and is this better than normal wear and tear through shooting a lot first. I think finish lapping the barrels is good, smooth finish precludes too much of copper deposits and helps easier cleaning. Break in helps the throat. Too much of any of this and you have worn more material away and shortened the barrel life. How long does your match barrel last? How many do you go through in a season? Do you buy 1 new barrel every 3 years or more or do you buy 30 at beginning of every season and pick 2 or 5 best ones of the bunch and discard the rest? Do you pay for these or are you sponsored or get a huge discount. Is fraction of MOA accuracy more important than long life of the barrel? Etc. Etc.

I still feel:
  1. some/proper (you tell me what is really proper) break-in is not harmful and probably helps
  2. hunting rifle barrel will also benefit but benefits may be less noticeable/needed
  3. fire/heat and melting/evaporation of the metal particles and the chemical reactions when burning primer/powder in the barrel is more harmful to the barrel than a bit of cleaning by hand
  4. Braking-in of match barrels is to prep the barrel for its shooting life and achieve best result and consistency asap without wearing/harming the barrel by firing hundreds of shots first
 
The nice thing about hand lapping is that you can feel what you're doing and therefore can, in my opinion/experience, better control the outcome.
 

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Hello Moe324
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